WO2018168663A1

WO2018168663A1 - Infrared sensor

Info

Publication number: WO2018168663A1
Application number: PCT/JP2018/009090
Authority: WO
Inventors: 平野　晋吾; 敬治白田
Original assignee: 三菱マテリアル株式会社
Priority date: 2017-03-15
Filing date: 2018-03-08
Publication date: 2018-09-20
Also published as: TW201842309A; JP2018151340A

Abstract

Provided is an infrared sensor capable of suppressing the influence of infrared radiation or heat from a lower substrate or a stem member and suppressing deterioration of detection accuracy. The infrared sensor according to the present invention comprises: a lower wiring substrate 11; a sensor mounting member 12 disposed on the lower wiring substrate; and an infrared sensor body 13 disposed on the sensor mounting member. The infrared sensor body is provided with: an insulating substrate 2; thermosensitive elements 3A, 3B provided on the insulating substrate; and an upper pattern wiring formed on the insulating substrate. The sensor mounting member is provided with a mounting member body, and a connecting member. The lower wiring substrate is formed in a quadrangular shape, and the sensor mounting member is formed in a quadrangular or substantially quadrangular shape having two mutually parallel sides 12a. In a state in which the lower wiring substrate and the sensor mounting member are aligned about a central axis C, the two parallel sides are disposed parallel to one of diagonal lines L1 of the lower wiring substrate, and the corner of the lower wiring substrate protrudes from the parallel two sides of the sensor mounting member in a plan view.

Description

Infrared sensor

The present invention relates to an infrared sensor that detects an infrared ray from a measurement object and measures a temperature or the like of the measurement object.

Conventionally, an infrared sensor is used as a temperature sensor that detects the temperature of an object to be measured by detecting infrared rays radiated from the object to be measured in a non-contact manner.
For example, Patent Document 1 describes an infrared sensor in which a measuring infrared sensor element and a compensating infrared sensor element are housed in a metal cap having an infrared incident window.
In this infrared sensor, the substrate on which the measurement infrared sensor element is mounted is installed so as to cover the upper side of the substrate on which the compensation infrared sensor element is mounted.

Patent Document 2 discloses a container having an incident window through which infrared rays are incident, a first infrared detecting element disposed opposite to the incident window in the container, a substrate on which the first infrared detecting element is mounted, An infrared detector is described that includes a second infrared detection element that is disposed under the substrate and shields infrared rays from an incident window.
Also in this infrared detector, similarly to the infrared sensor of Patent Document 1, the substrate on which the first infrared detection element is mounted covers the upper side of the substrate on which the second infrared detection element is mounted.

JP-A 64-32131 Japanese Patent Laid-Open No. 11-132857

The following problems remain in the conventional technology.
In the above prior art, the infrared detecting and compensating thermosensitive elements are mounted on mounting boards such as separate printed circuit boards, and these mounting boards are supported by support columns with a space above the stem member. ing. For this reason, there is a problem that the detection-side mounting board on which the thermal element for detecting infrared rays is mounted receives infrared rays radiated from the lower compensation-side mounting board, and the detection accuracy is lowered. In particular, since the mounting board on the detection side is arranged above so as to cover the entire top surface of the mounting board on the compensation side, it receives infrared rays from the entire top surface of the mounting board for compensation, and the infrared detection accuracy is high. It had fallen. Furthermore, since the compensation-side mounting board is arranged on the stem member, it receives infrared rays from the stem member affected by external temperature changes, and the infrared rays due to the heat affect the upper detection-side mounting board. There was an inconvenience.

The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an infrared sensor capable of suppressing the influence of infrared rays and heat from a lower substrate and a stem member and suppressing a decrease in detection accuracy. And

The present invention employs the following configuration in order to solve the above problems. That is, the infrared sensor according to the first invention is provided on the lower wiring board on which at least a pair of lower pattern wirings are formed, the sensor mounting member installed on the lower wiring board, and the sensor mounting member An infrared sensor body, wherein the infrared sensor body is an insulating substrate, at least one thermal element provided on the insulating substrate, and at least a pair of thermal elements formed on the insulating substrate and connected to the thermal element. An upper pattern wiring, wherein the sensor mounting member is an insulating mounting member main body, and is provided in the mounting member main body and connected to the upper pattern wiring and at least a pair of the lower pattern wiring The lower wiring board is formed in a square shape, and the sensor mounting member has at least two sides parallel to each other. Are formed in a rectangular shape or a substantially rectangular shape, and the parallel two sides are arranged in parallel with one of the diagonal lines of the lower wiring substrate in a state where the central axis coincides with the lower wiring substrate, A pair of corners at least diagonally of the lower wiring board protrude from the two parallel sides of the sensor mounting member in plan view.

Since this infrared sensor includes a lower wiring board, a sensor mounting member installed on the lower wiring board, and an infrared sensor main body installed on the sensor mounting member, the lower wiring board and the infrared sensor main body A sensor mounting member is interposed therebetween, which shields and insulates infrared rays and heat from the lower wiring board, and makes the infrared sensor main body thermally independent to suppress a decrease in detection accuracy. Further, since the pair of corners at least diagonally of the lower wiring board protrude from the two parallel sides of the sensor mounting member in a plan view, the sensor mounting member and the lower wiring board are positioned vertically (in a plan view). ) The presence of the non-overlapping portion weakens the thermal coupling between the lower wiring board and the sensor mounting member, makes it less susceptible to the influence from the lower wiring board, and can suppress a decrease in detection accuracy.

An infrared sensor according to a second invention is characterized in that, in the first invention, the lower wiring board and the sensor mounting member are both substantially square.
That is, in this infrared sensor, since the lower wiring board and the sensor mounting member are both substantially square, the diagonal lines of the lower wiring board and the sensor mounting member are deviated from each other by 45 degrees and overlap each other. Since the corners protrude from the four sides of the member, thermal coupling between the lower wiring board and the sensor mounting member can be further weakened. In addition, since the portions that do not overlap each other are symmetrically arranged in all directions, the heat conduction becomes uniform and the detection error can be reduced. In addition, if the lower wiring board and the sensor mounting member as a whole have a basic shape or a schematic shape that is a square shape, the outer peripheral portion may have a cutout, and is assumed to have a substantially square shape.

An infrared sensor according to a third invention is the infrared sensor according to the first or second invention, wherein the connection member is provided to project upward from the mounting member body, and the infrared sensor body is disposed between the mounting member body and the infrared sensor body. It is characterized by being fixed to the upper end of the connecting member with a gap left.
That is, in this infrared sensor, since the infrared sensor main body is fixed to the upper end portion of the connecting member with a gap between the mounting member main body, the infrared sensor main body is in a state of floating from the mounting member main body, Heat from the mounting member main body becomes difficult to be transmitted to the infrared sensor main body, and a decrease in detection accuracy can be further suppressed.

An infrared sensor according to a fourth aspect of the present invention is the infrared sensor according to any one of the first to third aspects, wherein the lower wiring board, the sensor mounting member, and the infrared sensor body are installed on a metal stem member, The stem member is insulated and sealed with sealing glass and is hermetically held in a penetrating state, and has at least a pair of lead wires electrically connected to the pair of lower pattern wirings, and an infrared incident window and A metal cap that houses the lower wiring board, the sensor mounting member, and the infrared sensor main body and is fixed on the stem member and hermetically seals the top of the stem member is provided.
That is, since this infrared sensor includes the stem member, the lead wire, and the cap, hermetic sealing is performed with the lower wiring board, the sensor mounting member, and the infrared sensor main body hermetically sealed in the cap. It can be easily mounted on another substrate by the lead wire.

The present invention has the following effects.
That is, the infrared sensor according to the present invention includes the lower wiring board, the sensor mounting member installed on the lower wiring board, and the infrared sensor main body installed on the sensor mounting member. The member can shield and insulate infrared rays and heat from the lower wiring board. Furthermore, since the pair of corners at least diagonally of the lower wiring board protrude from the two parallel sides of the sensor mounting member in plan view, the thermal coupling between the lower wiring board and the sensor mounting member is weakened, It is more difficult to be affected by the wiring board, and a decrease in detection accuracy can be suppressed.

In 1st Embodiment of the infrared sensor which concerns on this invention, it is a top view which shows the state before attaching a cap. In 1st Embodiment, it is schematic sectional drawing which shows an infrared sensor. FIG. 2A is a plan view showing a state where an infrared sensor main body is installed on a sensor mounting member in the first embodiment, and FIG. In 1st Embodiment, it is a top view which shows a sensor mounting member. In 1st Embodiment, it is a side view which shows a sensor mounting member. In 1st Embodiment, it is a reverse view which shows an infrared sensor main body. In 2nd Embodiment of the infrared sensor which concerns on this invention, it is a top view which shows the state before attaching a cap. It is explanatory drawing which shows the positional relationship of a lower wiring board and a sensor mounting member in the other example of the infrared sensor which concerns on this invention.

Hereinafter, a first embodiment of an infrared sensor according to the present invention will be described with reference to FIGS. 1 to 6.

As shown in FIGS. 1 to 3, the infrared sensor 1 according to the present embodiment includes a lower wiring board 11 on which two pairs of

lower pattern wirings

11 a and 11 b are formed, and a sensor mounting member installed on the lower wiring board 11. 12 and an infrared sensor main body 13 installed on the sensor mounting member 12.
In addition, the infrared sensor 1 of the present embodiment includes a metal stem member 14 in which a lower wiring board 11, a sensor mounting member 12, and an infrared sensor main body 13 are installed at an upper portion, and a sealing glass 15a in the stem member 14. Two pairs of lead wires 15 that are insulated and sealed and are airtightly held and electrically connected to two pairs of

lower pattern wirings

11a and 11b, an infrared incident window 16a, and a lower wiring substrate 11 The sensor mounting member 12 and the infrared sensor main body 13 are accommodated, and a metal cap 16 that is fixed on the stem member 14 and hermetically seals the stem member 14 is provided.

As shown in FIG. 6, the infrared sensor body 13 includes an insulating substrate 2, a pair of

thermal elements

3A and 3B provided on the insulating substrate 2, and

thermal elements

3A and 3B formed on the insulating substrate 2. Two pairs of

upper pattern wirings

21A and 21B connected to each other are provided.
The sensor mounting member 12 includes an insulating mounting member main body 6 and two pairs of connections provided on the mounting member main body 6 and connected to the

upper pattern wirings

21A and 21B and to the

lower pattern wirings

11a and 11b. And a member 7.

The lower wiring board 11 is formed in a square shape. In the present embodiment, the lower wiring board 11 of a printed board formed in a square shape is employed.
The sensor mounting member 12 is formed in a quadrangular or substantially quadrangular shape having at least two sides 12a parallel to each other. In the present embodiment, the sensor mounting member 12 having a substantially square shape in plan view is employed. In addition, as shown in FIG. 3, if the basic shape is a quadrangle or a substantially quadrangular shape, there may be a notch. The substantially quadrangular shape in the present invention includes a shape having at least two sides parallel to each other and an arc shape on the other two sides, or a shape obtained by cutting off corners of the quadrangle with an arc or a straight line. The overall shape is generally rectangular.

The sensor mounting member 12 is installed with the two parallel sides 12a arranged in parallel with one of the diagonal lines L1 of the lower wiring board 11 in a state where the central axis C coincides with the lower wiring board 11. A pair of corner portions 11c at least diagonally protrude from the two parallel sides 12a of the sensor mounting member 12 in plan view.
In particular, in this embodiment, since the lower wiring board 11 and the sensor mounting member 12 are both substantially square, the four corner portions 11c protrude from the sides of the sensor mounting member 12 in plan view.

The connecting member 7 protrudes upward from the mounting member main body 6, and the infrared sensor main body 13 is fixed to the upper end portion of the connecting member 7 with a gap between the connecting member main body 6 and the infrared sensor main body 13.
Two pairs of terminal electrodes 4 are formed on the insulating substrate 2.
The mounting member body 6 is formed of an insulating material such as resin.
The connection member 7 is attached to the mounting member main body 6 and has an upper end connected to the terminal electrode 4 by soldering or the like and a lower end connected to the

lower pattern wirings

11a and 11b by soldering or the like.

As shown in FIG. 3, the connection member 7 is formed of a conductive material such as a metal having higher thermal conductivity than the mounting member main body 6, and has a terminal pin portion 7 a protruding sideways. .
The mounting member body 6 includes a connecting member hole 6a formed on the side and into which the terminal pin portion 7a is inserted and fixed, and a connecting member hole 6a formed on the upper portion and directly below the

thermal elements

3A and 3B. And an element accommodating hole 8 communicating with 6a.
That is, the terminal pin part 7a which protruded long is fixed by being inserted and fitted in the long hole-shaped connection member hole 6a.

The tip of the terminal pin portion 7a protrudes into the element housing hole 8.
The element housing hole 8 penetrates up and down the mounting member body 6 so that the first heat sensitive element 3A and the second heat sensitive element 3B can be accommodated. In addition, in order to shield the infrared rays radiated from the lower wiring substrate 11, the element housing hole 8 may be a bottomed hole.
As shown in FIGS. 4 and 5, the mounting member main body 6 has a thin portion 6 b formed thinner than other portions excluding the element housing hole 8. The thin portion 6 b is a hole provided in the center of the mounting member body 6 in a rectangular shape in plan view.

In the present embodiment, the mounting member main body 6 has a thin plate-like block shape formed in a substantially square shape in plan view, and the four connection members 7 are installed in the vicinity of the four corners, two on each of the opposing sides. Connection members 7 are arranged one by one. That is, two portions for supporting the infrared sensor main body 13 are provided on both sides of the mounting member main body 6 at intervals from each other, and the infrared sensor main body 13 is supported and fixed at four locations.

The infrared sensor main body 13 is supported with a parallel gap provided between the mounting member main body 6 and the infrared sensor main body 13. That is, as described above, the upper portion of the connection member 7 protrudes from the upper surface of the mounting member main body 6 by a certain amount, and the infrared sensor main body 13 connected to the upper end portion by soldering or the like is lifted from the mounting member main body 6. I support in the state.

The connecting member 7 has a terminal slit portion 7c extending under the terminal pin portion 7a opposite to the protruding direction of the terminal pin portion 7a, and the mounting member body 6 is inserted into the terminal slit portion 7c. It has a portion 6c.
If the length from the base end of the terminal slit portion 7c to the tip of the terminal pin portion 7a is defined as the length of the terminal pin portion 7a, the terminal pin portion 7a is set to a length greater than the thickness of the mounting member body 6. Yes.

The terminal slit portion 7c is formed by being cut in the lateral direction so that the terminal insertion portion 6c can be inserted.
The lower end portion of the connecting member 7 is arranged on the inner side than both sides of the mounting member main body 6 in a state of being attached to the mounting member main body 6, and is set so as not to easily tilt as a whole.
The upper end portion and the lower end portion of the connecting member 7 are flat portions for soldering.
The connecting member 7 has a plate shape formed from a metal plate by die cutting, etching, or laser processing.

As shown in FIG. 6, the infrared sensor main body 13 has a pair of thermal elements 3 </ b> A and 3 </ b> B (first and second thermal elements 3 </ b> A and 2 </ b> A) provided on one surface (lower surface) of the insulating substrate 2. And the

upper pattern wirings

21A and 21B formed on one surface of the insulating substrate 2 (a pair of first pattern wirings 21A that are conductive metal films connected to the first thermal element 3A). And a pair of second pattern wirings 21B), which are conductive metal films connected to the second thermal element 3B, and provided on the other surface of the insulating substrate 2 so as to face the second thermal element 3B. And an infrared reflection film 22.
In FIG. 3, the infrared reflecting film 22 is hatched.

In addition, the first pattern wiring 21A and the second pattern wiring 21B are connected to a pair of adhesive electrodes 23 formed on the insulating substrate 2 at one end, respectively, and insulative at the other end. A terminal electrode 4 formed on the substrate 2 is connected.
In addition, the terminal portions of the corresponding first thermal element 3A and second thermal element 3B are bonded to the adhesive electrode 23 with a conductive adhesive such as solder.

The insulating substrate 2 is formed of an insulating film such as a polyimide resin sheet, and the infrared reflecting film 22, the first pattern wiring 21A, and the second pattern wiring 21B are formed of copper foil. That is, these are double-sided flexible, in which the infrared reflecting film 22, the first pattern wiring 21A, and the copper foil electrodes used as the second pattern wiring 21B are patterned on both surfaces of the polyimide substrate used as the insulating substrate 2. It is produced by a substrate.

The infrared reflection film 22 is arranged in a substantially square shape immediately above the second thermal element 3B.
The infrared reflection film 22 is formed of a material having an infrared reflectance higher than that of the insulating substrate 2 and is formed by applying a gold plating film on the copper foil. In addition to the gold plating film, for example, a mirror-deposited aluminum vapor deposition film or an aluminum foil may be used. The infrared reflective film 22 is formed to cover the second thermal element 3B with a size larger than that of the second thermal element 3B.

The first thermal element 3A and the second thermal element 3B are chip thermistors in which terminal portions are formed at both ends. As this thermistor, there are thermistors of NTC type, PTC type, CTR type and the like. In this embodiment, for example, NTC type thermistors are employed as the first thermal element 3A and the second thermal element 3B. This thermistor is made of a thermistor material such as a Mn—Co—Cu-based material or a Mn—Co—Fe-based material.

As described above, the infrared sensor 1 of the present embodiment includes the lower wiring board 11, the sensor mounting member 12 installed on the lower wiring board 11, and the infrared sensor main body 13 installed on the sensor mounting member 12. Therefore, the sensor mounting member 12 is interposed between the lower wiring board 11 and the infrared sensor main body 13, shields and insulates infrared rays and heat from the lower wiring board 11, and heats the infrared sensor main body 13 thermally. A decrease in detection accuracy can be suppressed independently.

Further, since the pair of corner portions 11c at least diagonally of the lower wiring board 11 protrude from the two parallel sides 12a of the sensor mounting member 12 in plan view, the sensor mounting member 12 and the lower wiring board 11 are connected to each other. Since there is a portion that does not overlap vertically (in plan view), the thermal coupling between the lower wiring board 11 and the sensor mounting member 12 is weakened, and is less susceptible to the influence from the lower wiring board 11, and the detection accuracy is reduced. Can be suppressed.

In addition, since the lower wiring board 11 and the sensor mounting member 12 are both substantially square, the diagonal lines L1 between the lower wiring board 11 and the sensor mounting member 12 are shifted from each other by 45 degrees and overlap each other. Since the corners 11 c protrude from the four sides of the mounting member 12, thermal coupling between the lower wiring substrate 11 and the sensor mounting member 12 can be further weakened. In addition, since the portions that do not overlap each other are symmetrically arranged in all directions, the heat conduction becomes uniform and the detection error can be reduced.

Further, since the infrared sensor main body 13 is fixed to the upper end portion of the connection member 7 with a gap between the infrared sensor main body 13 and the mounting member main body 6, the infrared sensor main body 13 is in a state of floating from the mounting member main body 6. Heat from the mounting member main body 6 becomes difficult to be transmitted to the infrared sensor main body 13, and a decrease in detection accuracy can be further suppressed.
Furthermore, since the infrared sensor 1 of the present embodiment includes the stem member 14, the lead wire 15, and the cap 16, the lower wiring substrate 11, the sensor mounting member 12, and the infrared sensor main body 13 are hermetically sealed in the cap 16. In a stopped state, it can be easily mounted on another substrate by the hermetically sealed lead wire 15.

Next, a second embodiment of the infrared sensor according to the present invention will be described below with reference to FIG. In the following description of each embodiment, the same constituent elements described in the above embodiment are denoted by the same reference numerals, and the description thereof is omitted.

The difference between the second embodiment and the first embodiment is that, in the first embodiment, the lower wiring board 11 and the sensor mounting member 12 having a substantially square shape in plan view are adopted. In the infrared sensor, as shown in FIG. 7, two sides 32b other than the two sides 32a parallel to each other among the four sides of the sensor mounting member 32 are arcuate.
That is, in the second embodiment, the two sides 32b of the sensor mounting member 32 have an arc shape along the inner peripheral surface of the cap 16, and the sensor mounting member 32 has a substantially rectangular shape in plan view.
Therefore, in the second embodiment, only the pair of corner portions 11c protrude from the two sides 32a of the sensor mounting member 12, and the infrared light receiving area is reduced while weakening the thermal coupling between the lower wiring board 11 and the sensor mounting member 32. Can be bigger.

The technical scope of the present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention.

For example, in the above-described embodiment, a heat sensitive element of a chip thermistor is employed, but a heat sensitive element formed of a thin film thermistor may be employed.
As the thermal element, a thin film thermistor or a chip thermistor is used as described above, but a pyroelectric element or the like can be used in addition to the thermistor.

In the first embodiment, the lower wiring board and the sensor mounting member having a substantially square shape in plan view are employed, but a rectangular sensor mounting member may be employed. In this case, as shown in FIG. 8, when the two parallel sides 32a of the rectangular sensor mounting member 32 are arranged parallel to the diagonal line L1 of the square lower wiring board 11, four corners are provided. Pairs facing each other in the portion 11c protrude from each side of the sensor mounting member 32 with the same protrusion amount. In addition, by setting the long side of the sensor mounting member 32 to be shorter than the diagonal length of the lower wiring substrate 11, all the four corner portions 11c can be protruded.

DESCRIPTION OF SYMBOLS 1 ... Infrared sensor, 2 ... Insulating board, 3A, 3B ... Thermal element, 6 ... Mounting member main body, 7 ... Connection member, 11 ... Lower wiring board, 11a, 11b ... Lower pattern wiring, 11A, 11B ... Upper pattern wiring 11c: Corners of the lower wiring board, 12 ... Sensor mounting member, 12a ... Two parallel sides of the sensor mounting member, 13 ... Infrared sensor body, 14 ... Stem member, 15 ... Lead wire, 15a ... Sealing glass, 16 ... Cap, 16a ... Infrared incident window, L1 ... Diagonal line of lower wiring board

Claims

A lower wiring board on which at least a pair of lower pattern wirings are formed;
A sensor mounting member installed on the lower wiring board;
An infrared sensor main body installed on the sensor mounting member,
The infrared sensor body includes an insulating substrate, at least one thermal element provided on the insulating substrate, and at least a pair of upper pattern wirings formed on the insulating substrate and connected to the thermal element,
The sensor mounting member includes an insulating mounting member main body, and at least a pair of connecting members provided on the mounting member main body and connected to the upper pattern wiring and connected to the lower pattern wiring;
The lower wiring board is formed in a square shape,
The sensor mounting member is formed in a quadrangular shape or a substantially quadrangular shape having at least two sides parallel to each other, and the parallel two sides of the lower wiring substrate are aligned with a central axis of the lower wiring substrate. Placed parallel to one of the diagonals,
An infrared sensor, wherein at least a pair of corner portions of the lower wiring board protrude from the two parallel sides of the sensor mounting member in a plan view.
The infrared sensor according to claim 1,
The infrared sensor, wherein the lower wiring board and the sensor mounting member are both substantially square.
The infrared sensor according to claim 1,
The connection member is provided to protrude upward from the mounting member body;
The infrared sensor, wherein the infrared sensor main body is fixed to an upper end portion of the connection member with a gap between the mounting member main body and the infrared sensor main body.
The infrared sensor according to claim 1,
A metal stem member in which the lower wiring board, the sensor mounting member, and the infrared sensor main body are installed at an upper portion;
At least a pair of lead wires insulated and sealed with sealing glass in the stem member and hermetically held in a penetrating state and electrically connected to the pair of lower pattern wirings;
A metal cap that has an infrared incident window and houses the lower wiring board, the sensor mounting member, and the infrared sensor body, and is fixed on the stem member and hermetically seals the stem member; An infrared sensor characterized by comprising: